Checkboxes not working

I have kind of a weird situation here at work. I have an '.xlsm' workbook that has a number of macros built into it. One of the sheets in it has many, many lines. We have check boxes beside each line so that after you check them off and then you can run a macro to hide all non-checked lines. I have had it working on previous machines and when I send the file to others in the office, they are able to use the checkboxes without issue. I have tried the following solutions...all with no luck.

- save as a new file
- ensure 'enable content' was selected when opening the file
- through trust center I have opened everything up so there are no active x and macro restrictions
- added the file location to the trusted center.

Just for further information, I can go in to developer mode and make modifications to the checkboxes or other active x controls.

Hoping someone knows what else I can look at here!

I will have to check and see if it is okay to send the file...proprietary information and all...

I will say though that I would normally agree that the code is where the problem likely lays except that everyone else that I send the file too doesn't have any issues and everything runs as expected which leads me down the road of a 'machine' or 'permission' issue.

Are the links in place - with a copy of the file - delete the checkboxes and try adding again

Option Explicit
Sub DelCheckBox()
ActiveSheet.CheckBoxes.Delete
End Sub
Public Sub chbox_forRows()'''                        Adds a checkbox to each row between two row numbers
Dim Frow As Variant: Dim Lrow As Variant
Dim i As Long
Dim str As String
str = InputBox("Enter first and Last row separated by -")
Frow = InStr(str, "-")
Frow = Left(str, Frow - 1)
Lrow = Right(str, Len(str) - InStr(str, "-"))
For i = Frow To Lrow
XAddCheckBoxes Cell:=Range("A" & i)
Next
End Sub
Private Sub XAddCheckBoxes(Cell As Range)
   With ActiveSheet.CheckBoxes.Add(Cell.Left, _
                                   Cell.Top, _
                                   Cell.Width, _
                                   Cell.Height)
      .LinkedCell = Cell.Offset(, 0).Address
      .Caption = Range(.LinkedCell).Row
   End With
End Sub

Thank you all...sometimes you need to go back to the basics. I did an office update and that has solved the issue.